I face the same problem as well... quite recently one of my colleague was asked to write a program to set up our server environment. He started to do it in shell script and asked me couple of doubts in shell scripts. I inturn asked him to do this application in perl because it will be much better.
I offered to help him in learning perl as well but he went ahead with his shell script giving lame excuses like 'perl is not a good choice because on some platforms perl is not available'. Well we use HP UX and I checked that perl was installed on both the development and production servers.)
I only wish that I had more convincing abilities so that I can convince people to learn and do perl for applications where perl is most suitable.